I was born in Zambia at the height of the Soweto uprisings to a South African father and a Zimbabwean mother. Both my parents were political activists, my father with the African National Congress's military wing, Umkhonto we Sizwe, and my mother with the then Zimbabwean African People's Union (Zapu), so for many years we were banned from either country. We moved to Zimbabwe after independence but being South African was a strong part of my identity and I longed to go there.

FW de Klerk's sudden announcement of Nelson Mandela's impending release on 2 February 1990, and the unbanning of the ANC and the Pan Africanist Congress, therefore, came as a thrilling surprise to a 14-year-old keen to get to grips with her heritage. I could finally, for the first time, go to the land I called my own.

Johannesburg took my breath away. The city was massive. It reminded me a lot of London, which I had visited at the age of 12. I was astounded. I went to live with my father's cousin and his family. Uncle Velile, Aunt Tembi and their children became the extended family I had dreamt of having. I was a few months short of 18 when South Africa's first democratic elections took place in 1994. Never before (or since) have I wished so much to be older. Watching the country queue up and vote was like standing outside a glass house where there is a major bash going on and not being able to get in. It felt like a good time to be South African but I still didn't feel firmly rooted.

The post-election decade saw me becoming an Afropolitan, studying in Hawaii, staying in England, travelling in Europe. My father died, I went back for the funeral and realised home really was where the heart was. With no job prospects, I decided to move back to South Africa. Part of the reason was that getting back during Thabo Mbeki's first term, I found a country that told me it was OK to be African, where I could be anything I wanted to be, where I was not a representative of my race or my continent but an individual free to be me – whoever I wanted me to be. I finally felt the peace of homecoming.

I found I was free to write what I wanted and to criticise the political leadership, yet be no less respected for it. I loved the multiple stories that South Africa had to tell because of its multiple cultures.

Then, in 2008, Johannesburg burnt: a wave of murderous attacks was unleashed on immigrants from other African countries who had become scapegoats for social problems such as unemployment, crime and lack of housing. For the first time in my life, I felt ashamed to be South African. No amount of poverty or unemployment could excuse people laughing as a man was necklaced with a tyre and burnt just because he was not South African. Nor could it explain the looting and pillaging.

The silence from the political leadership was deafening. Like all middle-class black people, I sought an explanation. I wrote of my rage on my blog and was shocked to receive a threatening call from someone close to power. "You are being counter-revolutionary," the voice on the other end of the line told me. I had known this man for three years and thought of him as a friend; writers were no longer as free as I had thought.

I am not totally pessimistic, though. I know that for every motor mouth like Julius Malema, the president of the ANC's Youth League, there are five South Africans who do not excuse their failings by flashing the race card. I know that for every Eugene Terre'Blanche, there are 10 employers who treat their staff with respect. I also know that for every white person who packs his bag and leaves because the country is "going to the dogs", there is a Kevin Bloom keen to roll up his sleeves and make the best of this country he calls home. Bloom is a South African writer whose cousin was murdered in a senseless killing in Cape Town. His book, Ways of Staying (Granta), talks of his decision to stay in the country.

A South Africa that fails (except perhaps in football) is not an option, and there are many South Africans like me who will not allow that to happen.